Motor has 1 1/2 gallon through it and now is making a humming sound and is not making any bottom to me sounds like a bearing..could it also be worn bushings on the rod?? Just strange for 11/2 gallon and was never over reved .........

Whatever you do, If you think it has a whining type bearing noise do not keep running it as you will only further damage the rest of the engine

Have someone inspect the engine if your not confident yourself, Replace the bearing if need be

If you did have to replace it have a good look at it for rusting and be honest with yourself about weather or not your after run technique (if you do so) could be letting your bearings fail early

Also have a good look at the crank portion that is exposed to the air/fuel charge from your carb (when the crank's intake port is not lined up) and see if it is scored from fine dirt or dust ingestion, You may also want to inspect your front bearing for dirt


Another thing to look into will be your fuel, see if anyone using the same batch has had problems etc

Just because the engine has oil in it when you stop it after idling does not necessarily mean that the lubrication package is looking after your bearing in high rpm / Load and or heat situations


And if you cant find any other obvious issues it may be fair to say you got a not so good bearing from Novarossi... it can happen and does with all engine brands at times but firstly have some one look at the engine who knows a little about it before you want to blame Novarossi for a bad bearing (not that im saying that you are doing so or don't know what your looking at)


I have often seen people wanting to blame Novarossi for a "bad bearing" when in fact upon pulling the engine down the engine has digested that much dirt its not funny, Or when the bearing shows obvious sings of rust!!

Or when the engine had been ran with a fuel that no one knows anything about...

1.6 Gal or six liters of fuel does not seem like allot of engine usage but if there is something upsetting a bearing that is doing close to 40.000 Rpm then it is huge

When you buy a high quality engine in particular like Novarossi i think its fair to say that the new factory installed bearing has absolutely nothing wrong with it and it is then only running conditions or maintenance issues which cause it to fail.. at least 99% of the time anyway

Also, & particularly in Offroad racing we have a huge amount of variables on the track as far as engine loads and temps are concerned without even considering after run issues, So if one engine bearing lasts say 10-15 liters and another lasts 30-40 liters then we cant say that has anything to do with bearing quality from the factory.. specially with the load and rpm these things do


I don't mean to rant on but i have had one to many people lately want to complain about a "Bad Novarossi bearing" when the user in some cases DOES NOT EVEN RUN THEIR ENGINE OUT OF FUEL at the end of a race day!!

I think i MAY have had one genuine case for a premature bearing failure which is questionable in the past year / 100 odd Novarossi engines sold, That bearing is recent and yet to be inspected

Bottom line is if Novarossi are fitting bad bearings to engines we wont see a post in here once or twice a year questioning such, Instead we will start getting five a week...





Dave,

FUSION X ENGINES AUATRALIA

No bottom end is a 99% sure sign of a rear bearing.

Pull the motor down and inspect the bearings also check other parts like what Dave mentioned in earlier post.

Thank guys.. no not at all playing the blame game..was more just a question on the rod as far as the bushings possible wear.. but yall are def. Right won't know until I get home tonight and pull it down. Thank for the info will update asap...and trust me if I find something from my end I will let know. Novas are tops out and very hard to believe a bearing issue from them.. I do know ceramics will make noise but when it lost power on bottom I then thought rear bearing and then I thought could be bushings on rod worn I then thought over reved no then break in no......on and on.

Donald,

It's the fuel... That's now four rear premature bearing failures, all using the same batch of fuel. (David, Ryan, Kale and now you)

what kind of fuel do you run ?

I highly doubt your rod bushing will have any wear unless something was really wrong during run in like cold engine temps temps say under 190f for prolonged periods of time.. mind you if there does appear to be a lubrication issue with your fuel as mentioned below you may want to give it a really good looking at

Remember when you check the rod bushing that play in it when the piston is at top dead center is normal


Bingo!

I once saw a brand/ batch of fuel take out that many rear bearings its not funny

I often hear people lately at race tracks saying things along the lines of "fuels are all the same.. just buy whatever you can get cheapest"

Always remember your engine internals are only as good as the oil that lubricates them...

I believe it is worth staying with well known large name brands of fuel that are made in controlled lab type environments.. and with fuel importers that turn over lots of fuel and only sell what is relatively fresh stock



Dave,

FUSION X ENGINES AUSTRALIA

anyone used the novarossi rex as I plan to get the 7port, will it rev really high? and what pipe and manifold recommended?

I am not sure if any shops have this engine in stock yet, It sure looks like a high rever

Pipe wise i would guess a 2096 or 9901 with a short header unless it lacks a bit of bottom end torque and was say going in a Truck

I believe the sleeve is that of or similar to a Toro / Keep Off 7 but im sure the engine guru's will tell us all about it when they get one in their hands



Dave,

FUSION X ENGINES AUSTRALIA

Here available with limited unit. How's the keep off 7 perform? Suitable for small/medium or wide open track?

For mine the keep off 7 (in a buggy?) would be for more open or high traction tracks where you can utilize a fair amount of power

Everyone of course will have their own personal views on this but the way i see it is more often than not many racers including myself at times are over powering our cars to the point where it is hurting our lap times & consistency

I think if you are a very good racer who is always at the pointy end of the field or have tracks that genuinely need allot of power its different because in scenarios like that a less powerful engine may well hurt you, But for the most part (from what i see at least) most people gain better lap times and consistency when they get over the big power thing and instead set up an engine and clutch system that provides smooth controllable power delivery... particularly in Buggy




Dave,

FUSION X ENGINES AUSTRALIA

Thanks for ur valueble advise, here they have an insane track like a total of 200m with a high speed corner in the middle. I plan to get the nova rex 7port or 8port to run this track. For the pipe n manifold, which do you prefer?

Thanks in advance

I would think 2096/41021 because the 9901/41021 may lack top end. It all depends on on track and driving style for you.

I may still have some parts from a REX 3 Port from long ago.

Hey guys I am thinking of going back in to nitro again and I saw the nova bloody and locc nitro engine are these any good in a truggy I am looking to get a tekno nt48

If its all high speed with a massive straight then like Chris said the short and 2096, If you feel you need more low rpm punch then the 9901

Perhaps you could post a vid of the track and we can all view it and give our thoughts



Dave,
FUSION X ENGINES AUSTRALIA